Definition of charge - Understanding the Concept of Charge

Last day we saw how a charged balloon was attracting small metal piece and then we explained the mechanism.
Now the question is what if I suspend a piece of non-conductor instead of metal?
.....ha ha ha, Let’s see by experiment what happens, Oh My God! It’s again attracted means the fact is true even for non-conductors, but what about mechanism, non-conductors do not have free electrons. Think then how they are attracted by charged body. Here is an explanation-